Vol. 30, Issue 4, pp. 585-590

Abstract

The 4-n-alkyl-4`-cyanobiphenyls (nCB, n is the number of carbon atoms in alkyl radical n=5, 8) confined to porous glasses with four different mean pore sizes (2, 4, 54 and 90 nm) have been studied. Using FT MIR and NIR spectroscopy methods we have investigated the interaction of nC8 molecules with the pore surface. It has been shown that the interaction is accompanied by the formation of hydrogen bonds between the SiOH group on the glass pore surface and the cyano-group of the nCB monomer. This is demonstrated by the change in the position and shape of CN stretching and Q(C identical to N)+Q(C=C) combination bands in the vibrational spectra of confined nCB depending on pore size and the length of the alkyl tail. To the contrary, in the case of benzophenone confined to PG, weak π ...OH-Si hydrogen bonds are formed.